This post is sponsored by Hive Hugger. 

I have kept bees in San Diego, California, for 15 years. Here, the temperature rarely strays from 70°F, and our average nighttime lows for “winter” are seldom below 50°F. Since we have some of the mildest weather in the world, I never considered insulating my beehives. That is, until I read a study about how well-insulated wild bee nests are. Then, I began to wonder, could my bees benefit from a better-insulated hive? Read on to find out what I learned.

Why Temperature Matters

Honey bees must keep their brood nest around 97°F for their young to develop properly. They generate heat by clustering tightly together in winter, and in summer, they cool the hive by fanning their wings and collecting water. The more extreme the weather is, the more the bees have to exert themselves to manage their temperature. This means they eat a lot of honey to fuel these activities.

Wild Hives vs. Beekeeping Boxes

Research shows that wild beehives tend to have more stable nest temperatures than managed hives. This makes sense, since natural beehives are found in tree hollows, fallen logs, and rock cavities with thick, well-insulated walls. In comparison, the walls of the Langstroth hive are only ¾ of an inch thick. 

My Findings

I wanted to know what would happen if I added insulation to my hives. So, this past winter,  I purchased ready-made insulation kits from Hive Hugger and some temperature sensors and began collecting data.

After a week of temperature data, I was surprised to learn that in all but my strongest colonies, the interior hive temperature was not stable. Most of my colonies had fluctuating interior temperatures that mirrored the outside temperatures. Even in healthy colonies with good populations, the temperature dropped 15-20°F at night and then shot up again during the day. 

Cue the Insulation

Initially, I tried to DIY my own insulation, but the process was messy, it was difficult to fit the pieces together and all the high R-value sheets were extremely thick. I ended up with foam bits all over my driveway, and only then did I realize that the foam was infused with pesticides! It turns out most commercially available insulation is treated with pesticides and, therefore, not ideal for wrapping beehives.  I was delighted when I found Hive Hugger offers custom insulation kits for different Langstroth hive setups. I immediately ordered the triple medium set since I use all medium boxes. The side panels fit together beautifully and were easy to install. 

At first, I thought I might get away with only adding the top insulation panel above the inner cover because of my mild climate, but there was no significant improvement until I added side panel insulation. Once I did this, I was amazed at the change. The insulation raised the temperature 10-15°F! Plus, the fluctuations decreased from 20°F swings to 5°F swings or less!

The pink line is the hive’s interior temperature. The blue line is the outside temperature. The highlighted blue area is the period in which insulation was on the hive. San Diego, California, December 2024. 

Conclusion

There’s no doubt that insulation improves the bees’ ability to keep a stable nest temperature, even in my mild climate. All 5 of my test colonies made it to spring in good health. I am excited to continue my experiments with insulated beehives this coming winter.